Automatic DJ at EchoNest
At the EchoNest blog, they've posted 5 example mixes generated by their Auto DJ - the Auto DJ can automatically time-stretch or compress and align tracks to give a seemless playlist (anyone who's listened to shuffle play on an iPod knows how important that can be). Listen to the Beatles track - its pretty interesting to hear the different songs fade in and out - it almost sounds like a completely new Beatles song. It's pretty neat.
